Why is my sculpture growing sharp and edgy when I try to (for example) grow an arm from the main sphere? Or trying to extend something?
It seems you are sculpting a 3d mesh without any knowledge of 3d in general. I think you did not subdivide properly the mesh or activating Dyntopo in your paint brush tool panel. That cause a weird mesh deformation due to low face polygons number, a topology problem.Spenting some time in watch some ytube tutorials could be a good star point.